Chronotherapy in practice: the perspective of the community pharmacist

A Systematic Review of Utilisation of Diurnal Timing Information in Clinical Trial Design for Long QT Syndrome

Diurnal oscillations in human cardiac electrophysiology are thought to be under the control of the endogenous circadian clock. The incidence of arrhythmic events in patients with Long QT syndrome (LQTS) varies diurnally. The diurnal variation in QT interval has previously been identified as a potential for error in clinical trials which utilise ECG measurement. We performed a systematic review of clinical trials for LQTS to identify practice around specification of timing information for point electrocardiogram (ECG) measurements, analysis of continual ECG recordings ≥24 h, and drug delivery. Despite guidelines having been issued around the analysis of 24-h ECG recordings, we identify a lack of usage of detailed time of day information in trial design for LQTS studies, which has the potential to affect the interpretation of the results of drug trials. We identify that, in contrast, clinical trials for QT prolonging drugs demonstrate increased incorporation of time of day information of both QT analysis and drug dosing. We provide a visual portal to allow trial designers and clinicians to better understand timing of common cardiac-targeting drugs, and to bear this concept in mind in the design of future clinical trials.

Recent Advances in Chronotherapy Targeting Respiratory Diseases

Respiratory diseases contribute to a significant percentage of mortality and morbidity worldwide. The circadian rhythm is a natural biological process where our bodily functions align with the 24 h oscillation (sleep-wake cycle) process and are controlled by the circadian clock protein/gene. Disruption of the circadian rhythm could alter normal lung function. Chronotherapy is a type of therapy provided at specific time intervals based on an individual's circadian rhythm. This would allow the drug to show optimum action, and thereby modulate its pharmacokinetics to lessen unwanted or unintended effects. In this review, we deliberated on the recent advances employed in chrono-targeted therapeutics for chronic respiratory diseases.

Mapping genes for drug chronotherapy

Genome-wide association studies have been increasingly used to map and characterize genes that contribute to interindividual variation in drug response. Some studies have integrated the pharmacokinetic (PK) and pharmacodynamic (PD) processes of drug reactions into association mapping, gleaning new insight into how genes determine the dynamic relationship of drug effect and drug dose. Here, we present an evolutionary framework by which two distinct concepts, chronopharmacodynamics and heterochrony (describing variation in the timing and rate of developmental events), are married to comprehend the pharmacogenetic architecture of drug response. The resulting new concept, heterochronopharmacodynamics (HCPD), can better interpret how genes influence drug efficacy and drug toxicity according to the circadian rhythm of the body and changes in drug concentration.

COMPARISON OF INFLUENCE OF VARIOUS REGIMENS OF DRUG INTAKE ON 24 HOUR bLOOD PRESSURE, CENTRAL AORTIC PRESSURE AND VASCULAR WALL STIFFNESS IN SYSTEMIC HYPERTENSION PATIENTS WITH ISCHEMIC STROKE

Aim. To assess and compare the efficacy of combination antihypertension drugs influence with various dosage regimens during 24 hour, on the parameters of daily blood pressure (BP) profile, central aortic pressure (CAP) and vessel wall stiffness in arterial hypertension (AH) patients with ischemic stroke (IS).

Material and methods. To the study, 177 AH patients included, with IS within last 4 weeks. All patients were randomized to 3 groups depending on the regimen of antihypertensive drugs combination intake during 24 hours. At baseline and in 12 months of therapy all patients underwent 24 hour BP monitoring (ABPM), CAP measurement and vessel wall stiffness evaluation.

Results. In 8 weeks of antihypertension therapy, target pressure level achievement was significantly more common in b. i.d. valsartan (group 3) comparing to once daily in the morning (group 1) or evening (group 2) (p<0,05). In all groups there were statistically significant positive changes in ABPM, CAP and stiffness. Also, in the group 2 there was significantly (p<0,05) more prominent decrease of the main ABPM, CAP and stiffness parameters than in the group 1. Valsartan b. i.d. led to significantly more prominent (p<0,05) improvement of the main ABPM, CAP and stiffness parameters improvement comparing to both variants of its once daily regimens. In 12 months of chronopharmacotherapy, in all groups, there was significant (p<0,05) increase of “dipper” 24 hour BP profile patients. Differences of the groups of “dippers” and “non-dippers” by the 12th month of treatment were significant for 3rd and 1st (p=0,0004), 3rd and 2nd (p=0,04) groups with the benefit for group 3.

Conclusion. Two times a day or only evening intake of valsartan with thiazidelike diuretic in the morning facilitated more significant improvement of the main parameters of ABPM, CAP and vascular wall rigidity comparing to just morning intake. B.i.d. valsartan regimen led to significantly (p<0,05) more commonly reached target BP level, improved normalization of 24 hour BP in most of patients, led to more significant improvement of the main ABPM, CAP and vascular stiffness parameters comparing to once daily morning or evening regimen.

A short review of drug-food interactions of medicines treating overactive bladder syndrome

Background Overactive bladder syndrome is a condition where one or more of the symptoms such as pollakiuria, urgent need to urinate, nocturia and urinary incontinence is observed. Its prevalence ranges between 7 and 27 % in men and 9–43 % in women. The role of a pharmacist is to educate the patient on medications administration scheme, and drug interactions with particular food or food components. Aim of the review To assess a potential impact of food and fruit juice on the pharmacokinetic and therapeutic effects of medications used in treating overactive bladder syndrome. This information will enhance pharmaceutical care and is vital and helpful for pharmacists counseling their patients. Method In order to gather information on interactions of medications employed in bladder dysfunctions, the English language reports published in the PubMed, Embase, Cochrane and CINAHL database over the years 1996–2015 were studied. Additionally, other resources, namely drugs.com, Medscape, UpToDate, Micromedex, Medical Letter, as well as Stockley Drugs Interaction electronic publication were included in the study. The analysis also covered product data sheets for particular medicinal products. Results Meals and the consumption of grapefruit juice were found to exert a diversified effect on the pharmacokinetics of drugs employed in overactive bladder syndrome therapy. Neither tolterodine, nor mirabegron interact with food and citrus fruit juice, whereas darifenacin, fesoterodine, oxybutynin and solifenacin do interact with grapefruit and others citrus fruit juice. The effects of such interactions may potentially be negative to patients. Trospium absorption is significantly decreased by food. Conclusion For selected medicines used in treating bladder dysfunctions food and grapefruit juice consumption may significantly affect efficacy and safety of the therapy. All information on the topic is likely to enhance the quality of pharmaceutical care.

Timing of Administration: For Commonly-Prescribed Medicines in Australia

Chronotherapy involves the administration of medication in coordination with the body's circadian rhythms to maximise therapeutic effectiveness and minimise/avoid adverse effects. The aim of this study is to investigate the "time of administration" recommendations on chronotherapy for commonly-prescribed medicines in Australia. This study also aimed to explore the quality of information on the timing of administration presented in drug information sources, such as consumer medicine information (CMI) and approved product information (PI). Databases were searched for original research studies reporting on the impact of "time of administration" of the 30 most commonly-prescribed medicines in Australia for 2014. Further, time of administration recommendations from drug information sources were compared to the evidence from chronotherapy trials. Our search revealed 27 research studies, matching the inclusion and exclusion criteria. In 56% (n = 15) of the research studies, the therapeutic effect of the medicine varied with the time of administration, i.e., supported chronotherapy. For some medicines (e.g., simvastatin), circadian-based optimal administration time was evident in the information sources. Overall, dedicated studies on the timing of administration of medicines are sparse, and more studies are required. As it stands, information provision to consumers and health professionals about the optimal "time" to take medications lags behind emerging evidence.